Cutter bearing structure



June 14, 1932. l l, L, CHAMBERS 1,863,084

CUTTER BEARING STRUCTURE Original Filed March 15, 1950 /7 ATTORN'EYPatented June 14, 1932 i UNITED STATES PATENT OFFICE IRA L. CHAMBERS, OFGARBER, OKLAHOMA, ASSIGNOR TO GARBERTOOL COMPANY, F GARBER, OKLAHOMA, ACORPORATION 0F OKLAHOMA; E. A. REED, TRUSTEE OF THE GARBER TOOL COMPANY,BANKRUPT CUTTER BEARING STRUCTURE Original application filed March 15,1930, Serial No. 436,037. Divided and this application filed August 18,

1930. Serial No. 476,051.

, My invention relates to bits for rotary well drilling apparatus andmore particularly to bearing structure for drill bit cones of thischaracter adapted for rotation on the drill body, the ypresent inventionbeing a division 1 means for adequately lubricating the bit during itsrotation on the drill stem.

A further object of the invention is to provide means for firmlysecuring a cone 1n rotatable relation with a drill bit.

y In accomplishing these and other objects of my invention I haveprovided improved details of structure the preferred form of which isillustrated in the accompanying drawing, wherein:

F ig. 1 is a side elevation of the lower portion of a rotary drill bitincluding cones rotatably mounted on the body.

Fig. 2 is a vertical, central section through the bearing structure of acone and adjacent portions of the cone mounting. h

Fig. 3 is a perspective View of a locking ring and a bearing member orbushing 1n disassembled relation.

Referring more in detail to the drawing:

l designates a bit body adapted to be supported in the usual manner onthe lower end of a string of drill pipe and includes inner divergingplane faces 2 and 3 forming a socket 4. Secured to each of the faces 2and 3 or formed integrally therewith is an eX- ternally threaded shank 5for engaging the internally threaded socket 6 of a bearing member orbushing 7 including al reduced cylindrical neck portion 8, an annularflange 9 joined to saidneck portion by an outwardly tapering wall 10,and an outer end of the bushing comprising a frusto conical portion Asocket l2 adapted to serve as a chamber for lubricant is drilled intothe flange 9 and is connected to a cylindrical chamber 13 at the lowerend of the socket 6 by a port 14. An axial chamber 15 of less diameterthan the chamber 13 communicates through a tapered port 16 with a.further reduced port 17 opening through the outer end of the bushing.

A drill cone 18 for mounting on the bushing is' provided with a conicalrecess 19 complementary to the conical end portion of the bushing, therecess in the cone being coniparatively deep to reserve a spaceI 2O forlubricant between the base of the recess and the end of the .bearingmember when the cone is mounted thereon. The outer' end of the recesscomprises a cylindrical wall 21 conforming to the outer end of theannular flange E), and is further provided with a slightly enlarged andinternally threaded opening 22 separated from the wall 21 by an annulargroove 23.

A locking ring 24 having a downwardly tapered lower end wall 25complementary to the outwardly tapered wall 10 of the bea-ring member,is externally threaded as indicated at 26 for engaging the threadedopening 22 of the cone, the groove 23 being adapted to rcceive foreignparticles lodging in the threads and displaced therefrom as a result ofthreading of the cone on the locking ring.

Means for further preventing disengagement of the cone from the ringincludes a set screw 27 threaded into a lateral opening 28 of the conefor seating on the external threads on the locking ring. The cone isfurther provided with a threaded opening 29 aligning with the socket 12and serving as an inlet and as a supply chamber for lubricant fed intothe bushing when the socket 12 registers with said threaded opening, aplug screw 30 being threaded in the opening 29 for closing the openingand for forcing lubricant into the chambers of the bushing.

In order to facilitate secure mounting of the locking ring and cone onthe bearing member, sockets 31 are formed in the inner end wall of thering for receiving a wrench or tool employed for threading the ring inthe end of the cone.

Assuming a cone and bearing member to be constructed as described theprocedure for as- 9 sembling a cone on a bit body and the act-ion of thelubricant to insure smooth operation would be as follows:

After a bushing is inserted in the conical socket of a cone the lockingring is mounted over the neck portion of the bushing and is threadedinto the inner end of the cone until the bushing is firmly seated in thecone. A set screw is next threadedY into its respective VLubricantisforced into the socket 12 andv through the ports 14 into the chambers13, l5

' and 2O until each of the chambers have been completely filled,whereupon the plug screw 30 is threaded intov the filler opening toprevent escape of lubricant from the chambers.

Due to the pressure exerted on the lubricant in the Vfilter opening bythe plug screw, a small amount thereof is periodically fed into thesocket l2 as the cone rotates on the bushing, insuring adequatelubrication of the bearing structure throughout a long period ofservice.

What I claim and desire to secure by Let-y ters Patent is:

l. A device of the character described including a cone havingfa conicalsocket and a side port, a bearing member having atapered portion adaptedto rotatably engage the coni- Y cal wall of said socket to form achamber between the apex of the bearing member and the base of thesocket, the bearing member having a channel adapted to connect said portwith said chamber, and means for retaining the cone in rotativeengagement with said bearing member. i

2. VA device of the character described including a cone having aconical socket and a side port, a bearing member having a taperedportion adapted to seat in said socket to form a chamber between theapex of the bearing member and the base of the socket, and having achannel and intermediateV chambers adapted to connectsaid port with saidiirstnamed chamber, and means for retaining the cone in rotativeengagement with said bearing member. n

3. A device of the character described including a cone having aconicalsocket and a side port, a bearing member having a tapered portionadapted to seat in said socket to form a chamber between the apex of thebearing member Vand the base of the socket,-and having a channel andintermediate chambers adapted to connect said port with the iirstnamedchamber, said intermediate chambers decreasing successively, in diametertowardV the apex of. the bearing member, and means for retaining theconein rotative engagement with said bearing member. 'f

4. In a device of the character described in combination with a bit bodyhavingY a threaded shank, a cone having a conical socket and a siderport, a bearing member including a tapered portion adapted to seatinsaid socket and having a threaded axial opening for receiving saidshank, said bearing member having a chamber adjacent the axial openingand achannel leading from the chamber to said port, and means forretaining thejcone inrotative engagement with said bearing member.

5. In a device o-the character described in combination with a bit bodyhaving a threaded shank, a cone having a conical socket and a side port,a bearing member including a tapered portion adapted to seat in saidsocket to form' a chamber between the apex of the bearing member and thebase of the socket, and having a threaded axial opening for receivingsaid shank, said bearing member having a channel and intermediatechambers adapted to connect said port with said first-named chamber, oneof the intermediate chambers being formed at the base of said axialopening, and means for retaining the cone in rotative engagement withsaid bearing member.

In testimony whereof I athx my signature.

IRA L. CHAMBERS.

Y las

